New York, March 19 : Children previously infected with Covid-19 develop natural circulating antibodies that last for at least seven months, finds a new study. The study showed that while 96 per cent of those infected with Covid-19 continued to have antibodies up to seven months later, well over half (58 per cent) of the samples were negative for infection-induced antibodies at their third and final measurement. "These findings are important because the information we collected from children infected with Covid-19 didn't differ at all by whether a child was asymptomatic, the severity of symptoms, when they had the virus, were at a healthy weight or had obesity, or by gender. It was the same for everyone," said researcher Sarah Messiah from The University of Texas Health at Houston. For the study, published in the journal 'Pediatrics', the team examined data from 218 children across the state of Texas between the age of 5 and 19 who were enrolled in the Texas CARES survey that began in October 2020 to assess Covid-19 antibody status over time among a population of adults and children in Texas. The volunteers who enrolled for the study provided researchers with three separate blood draws. Samples were collected before the vaccine rollout and during the Delta and Omicron variants. To date, investigators have completed three different phases of the study. The researcher said that the results are just a step in understanding the virus' impact on children. To date, 14 million kids in the US have tested positive for the virus, she said. /IANS